BEIJING, CHINA -- Education authorities in east China say they smashed a ring that used high-tech radio transmitters and receivers to help students cheat in the national college entrance exams.

The ring involved at least 33 people, including nine high school graduates who sat the exams last month, providing answers to questions through the Internet and radios, said officials in Zhejiang Province.

The cheating was discovered when a surveillance patrol vehicle picked up radio transmissions near the Yongkang No.1 Middle School, where exams were being held, the Zhejiang-based City Express News reports on Sunday.

Law enforcement officers apprehended 15 people in a coffee bar across a river from the school. The others were caught in another two operations.

They allegedly admitted they had transmitted test answers to students who were sitting the exam. The suspects outside the exam site were parents or relatives of the nine students.

The students are alleged to have worn tiny earphones.

Three college students from Yongkang City are also being investigated for allegedly providing test answers via the Internet from southwest China's Guizhou Province.

One of the students surnamed Xu allegedly said he heard the answers could be provided for 12,000 yuan to 16,000 yuan ($1,740 to $2,320). Xu is also alleged to have paid 1,600 yuan for the specially-designed communication system, including a transmitter, receiver, earphone and walkie-talkies.

Xu allegedly said he used the device in the first test on Chinese, but did not use it again in the afternoon maths test because he had heard some had been caught cheating.

Under college entrance exam rules, cheating examinees will be denied college entrance for two years. Regulations in Zhejiang require instances of cheating to be permanently recorded in student files, which could affect their future credit records.

A record 10.5 million Chinese sat the national college entrance exams this year. Roughly half will get a place in college.